In general, a machine component such as a turbine rotor blade applied to a gas turbine engine will be subject to various repairs until coming to the end of its life. In a case where a defect such as a crack occurs to a portion to be repaired of the turbine rotor blade, the repairs are carried out in accordance with the following manner.
More specifically, the defect generated at the portion to be repaired of the turbine rotor blade is removed by grinding machining. Subsequently, a deposition is formed by cladding by welding at a removed portion from which the defect in the turbine rotor blade is removed. Thereby the turbine rotor blade as the machine component can be repaired and, in other words, a restored turbine rotor blade as a restored machine component can be produced from an original turbine rotor blade as an original machine component which is a subject of repair.